Such a heat exchanger is known from DE 20 2008 003 516 U1. It shows a cooling device for electronic components with plate on both sides provided with heat exchanger elements along the surface of which two separate air flow paths are located of which one is carrying external air and the other is carrying internal air. The cooling device has two inlets located in one plane which are in fluid connection. The two chambers are in fluid connection with ducts on the upper and lower side of the plate with the plate comprising at least one Peltier element.
Said cooling device is a compact device which can be inserted into a switch cabinet as a cassette and draws in cool external air through slots or openings of a switch cabinet. It is formed as an insertion element which is also adapted to standard switch cabinets with 19 inch rails.
From U.S. Pat. No. 4,926,935 A a heat exchanger is known where a thin-walled metal sheet is formed such that a plurality of ribs running in parallel, with flat upper and lower side, results. Subsequently, the metal sheet is formed transversely to the longitudinal direction such that their upper and lower sides each form a closed plane with abutting edges being connected with each other, for example by soldering. Thus, triangular ducts, separate from each other, are formed between the flat upper and lower sides. Said design is supposed to avoid the necessity of a base plate from which cooling ribs protrude.
The manufacture of ribbed plates can, for example, be taken from US 2009/0266127 A1.
U.S. Pat. No. 5,372,187 shows a double corrugated heat exchanger made from a continuous metal sheet. Due to the double corrugation, the effective surface area is supposed to be increased.
DE 102 33 736 B3 shows a heat exchanger with a substrate having a plurality of regularly positioned ducts extending through the substrate as well as bars protruding from an upper side of the substrate, the height of which corresponds at maximum to half of the length of the ducts in flow direction. A directed fluid flow runs tangentially to both sides of the substrate.
The bars are directed transversely to the flow direction and serve as a flow obstacle for producing turbulence zones which improve a heat transfer.
DE 10 2008 013 850 B3 shows an air-conditioning system for components located in a switch cabinet. The air-conditioning system comprises three ducts. The first duct serves as an external duct. A partition wall separates the external duct from a center duct, and a Peltier element provided on both sides with heat exchanger elements separates the center duct from an internal duct. By switchable flaps on the ends of the ducts, a first fluid can be guided through the external duct in a first operating mode and in a second operating mode through the center duct, with a second fluid in the first operating mode flowing through the center duct and in the second operating mode through the internal duct. In one operating mode an air/heat exchange occurs and in the second operating mode active cooling by the Peltier element occurs.